Closed Bug 1266126 Opened 4 years ago Closed 4 years ago

Improve Correspondents column's arrow icons

Categories

(Thunderbird :: Folder and Message Lists, defect)

defect
Not set

Tracking

(Not tracked)

RESOLVED FIXED
Thunderbird 50.0

People

(Reporter: wsmwk, Assigned: Paenglab)

References

(Blocks 1 open bug)

Details

(Keywords: ux-efficiency, ux-visual-hierarchy)

Attachments

(10 files, 6 obsolete files)

2.40 KB, image/png
wsmwk
: feedback-
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29.48 KB, patch
Paenglab
: review+
Details | Diff | Splinter Review
Do something to be more explicit about what the two arrows mean.

Currently the arrows are plain grey. Color differentiation?
Add some text on mouseover? (Personally I'd like to see this)
As mentioned elsewhere, I've tried to push the following rule for our UI:

Dynamic/status icons should always have a color associated with them. These icons represent the current state of an entity and need to be read by the user at a glance. They should also have different shapes (and alt text) for accessibility purposes. Using the same color for all the statuses here isn't appropriate since it increases the amount of time a user has to look at the entity to parse its current state.

Static icons can (and in our current theme, should) be greyscale. Since they don't move around (much), they don't generally indicate a status effect, and are primarily hotspots for clicking on things. Different icons still help here, but since they're static, they don't need to be parsed as quickly by the user.

By this logic, the <- and -> in the Correspondents header should have unique colors.

We may also want to use down (for incoming) and up (for outgoing) arrows instead, since left/right arrows traditionally refer to replies and forwards, respectively (both of which are actually outgoing messages).
http://forums.mozillazine.org/viewtopic.php?p=14576201#p14576201 mentions arrows, placing them to left or right
Attached image correspondents.png
This is a first shot. What do you think?
Attachment #8743433 - Flags: feedback?(vseerror)
Attachment #8743433 - Flags: feedback?(squibblyflabbetydoo)
Personally I prefer the right and left arrows. When I am viewing a list with both, I sort of mentally picture myself as sitting on the left, so the arrows make sense. Much hard to do that with up and down.
Comment on attachment 8743433 [details]
correspondents.png

I'm neutral on this. I definitely like it better than what we have now, but I have two concerns:

1) The colors are currently the same as the reply/forward icons' colors, which might be confusing (or maybe it's ok). For Aero, how about green for incoming and blue for outgoing? This matches the inbox/outbox icons in the folder pane.

2) While I prefer the up/down, I can see what :rkent means. One way to help this could be to make the icons look more like the inbox/outbox icons, which have a little picture of a bin. We could either reuse those icons, or make a version where the bin has less emphasis, since the more-important part is really the arrow.
Attachment #8743433 - Flags: feedback?(squibblyflabbetydoo)
To clarify, for (2), I mean that we should keep the existing inbox/outbox icons, but we might want to create *new* icons that look similar for the thread pane.

In any case, the inbox/outbox icons already establish that down means "incoming" and up means "outgoing".
(In reply to Jim Porter (:squib) from comment #6)
> down means "incoming" and up means "outgoing".

Yes, but the left and right arrow point "from" or "to" the correspondent in the list, thus is intuitively clearer than "up" or "done" (which works for the basket in the vertical folder list).

So, +1 for keeping the arrows' directions but colorizing them.
For whatever it's worth, it took me a long time to memorize what the left and right arrows mean because their context is implicit: my email address isn't shown, so the arrows don't explicitly show either a source (for outgoing) or a destination (for incoming). In fact, I originally looked at the arrows as independent from the text entirely, as with the other thread pane icons: the "reply" and "forward" icons don't rely on the position of the subject to inform the user of their meaning.

I suppose the same could be said for up/down arrow icons with a "bin" like the inbox/outbox, but the bin makes it clearer that the arrow is describing motion to/from that reference point. I can see an argument that "arrow + bin" is too heavyweight for a status indicator though.
I could make them diagonal, so both needs are satisfied. ;)
The icon shape and direction is ok with me.
The colour grey is barely visible and difficult to read. Please consider that some colourways toegter do not work for those with colour blindness.

Could you also put them in their own column so I can disable them without disabling the 'Correspondents' column. Strange as it may seem, I do not need to know I received the email because it actually says who the from in the Correspondent column. So a visual column of arrows is not required, hence the need to remove them.
(In reply to Jim Porter (:squib) from comment #6)
> To clarify, for (2), I mean that we should keep the existing inbox/outbox
> icons, but we might want to create *new* icons that look similar for the
> thread pane.
> 
> In any case, the inbox/outbox icons already establish that down means
> "incoming" and up means "outgoing".

I believe squib's idea is vastly clearer than just left/right or up/down arrows alone or any colors can convey, and is my prefered solution barring better suggestions. And therefore disagree with aceman's and kent's thinking.  

Practically every time I have looked at those arrows, I find myself rethinking is this an incoming or outgoing message.  (and this is especially important to me, because I have outoing messages in my Inboxes)

I don't beleive there should be a separate column - to me that would add confusion and complexity
Comment on attachment 8743433 [details]
correspondents.png

appreciated, but minus per my comments
Attachment #8743433 - Flags: feedback?(vseerror) → feedback-
I'm trying to remove duplication and save space
the icon will indicate incoming or outgoing.
The Correspondent info tells you who sent it anyway.
I do not need to be see this info twice, so one needs to go and that for me is the one thing that adds nothing to the info already present - the icon.

Some people use eg: 'All Mail' and therefore may want the icon because they cannot or do not want to use the sort for whatevcer reason. 

If people need this then the two should be separate, then everyone has exactly what they choose to require.
If I have an incoming email from jo bloggs then I know it is incoming because it says 'jo bloggs' in the correpondent column and it is in my Inbox as unread mail.   So I need the 'Correspondent' column but do not need any icon telling me hey this is an incoming email as that is blatantly obvious as all the info is already telling me this.

It is just adding confusion, duplication and wasting space in most folders with the exception of any folder that amalgamates incoming and outgoing. Most folders probably do not meet that requirement, so why design something to meet a specific requirement and then try to force it to work on every folder simply because it was designed lumped together when it should have been separate in the first place so fitting in with all senarios.


Another idea regarding icons as we are brainstorming ideas - we already use icons in the Folder Pane to denote 'Sent' and 'Inbox for incoming mail'.
As the only purpose of the current grey icons is to denote whether it was sent or incoming, why not just reuse those same Folder Pane icons instead of trying to invent something new which people may find confusing. I see no reason to reinvent the wheel when it already exists or reinvent the icon when it already exists. Thoughts ?
Attached image maiboxIcons.png
This is how it would look with the inbox/outbox icons. For me it doesn't work because the icons are too heavy for this purpose.
(In reply to Richard Marti (:Paenglab) from comment #14)
> Created attachment 8743914 [details]
> maiboxIcons.png
> 
> This is how it would look with the inbox/outbox icons. For me it doesn't
> work because the icons are too heavy for this purpose.

I was afraid that would happen. I agree.
Unless they can be simplified, I guess it's go with non-grey arrows.

I notice that mousing arrow does nothing.  What about tooltips on mouseover?
(Mousing over address text pops a tooltip if the contents are wider than the field, as expected)
Attached image diagonal.png
What about diagonal icons? In is now green.
(In reply to Wayne Mery (:wsmwk, use Needinfo for questions) from comment #15)
> 
> I notice that mousing arrow does nothing.  What about tooltips on mouseover?
> (Mousing over address text pops a tooltip if the contents are wider than the
> field, as expected)

I'm not so experienced in this but I look if I can do this. If not, Squib can hopefully help.
(In reply to Wayne Mery (:wsmwk, use Needinfo for questions) from comment #11)
> And therefore disagree with aceman's and kent's
> thinking.  

I don't think I voiced any opinion yet in this bug :)

I think I am fine with the up and down arrows. I am not sure the purple and blue colors as in picture 1 are different enough.

> Practically every time I have looked at those arrows, I find myself
> rethinking is this an incoming or outgoing message.  (and this is especially
> important to me, because I have outoing messages in my Inboxes)

Yes, me too.

> I don't beleive there should be a separate column - to me that would add
> confusion and complexity

It would allow to group/order by sent/received so it could have some value. But I do not advocate adding it right now.
The diagonal arrows are an interesting idea.
Let me make one more pitch for keeping the left and right arrows, just colored.

Really the intended interpretation of these, which I think makes more sense than up or down, is that it shows the direction of the email relative to the shown name. -> kent@caspia.com is to me, <- kent@caspia.com is from me. Once you understand that, the left and right make sense, and up and down do not.

I do not find confusion with forward and reply since, at least on my system, those are stylized with curves in the arrow, plus they appear next to subjects, not destinations.
Here's a 5-minute Photoshop of what I had in mind. There's a bin in the icon, but it's very simplified so it's not as "heavy" as the inbox/outbox icons. It could use some work to make it prettier, though.
(In reply to Kent James (:rkent) from comment #20)
> Really the intended interpretation of these, which I think makes more sense
> than up or down, is that it shows the direction of the email relative to the
> shown name. -> kent@caspia.com is to me, <- kent@caspia.com is from me. Once
> you understand that, the left and right make sense, and up and down do not.

My main issue is that that's not an obvious interpretation to me. In general, icons in Thunderbird aren't meant to depend on the relative position of the text they refer to; the icon can usually be read by itself.

If we stick with left/right arrows, we should also make sure that they work right for RTL locales.
Attached patch correspondents.patch (obsolete) — Splinter Review
This patch is still using the left/right directing arrows but colored now.
Assignee: nobody → richard.marti
Status: NEW → ASSIGNED
Attachment #8744645 - Flags: review?(squibblyflabbetydoo)
(In reply to Jim Porter (:squib) from comment #21)
> Created attachment 8743989 [details]
> Vertical icons and simplified bin
> 
> Here's a 5-minute Photoshop of what I had in mind. There's a bin in the
> icon, but it's very simplified so it's not as "heavy" as the inbox/outbox
> icons. It could use some work to make it prettier, though.

(sorry didn't comment earlier.)
I rather like squib's idea.
But maybe *colored* left/right arrows will grow on me.  No doubt more better with tooltips.
squib how is that accomplished?
Flags: needinfo?(squibblyflabbetydoo)
Sorry forgot to write my patch is without tooltip change. This, 1. because like this it's possible to uplift to 45 without th , 2. I haven't found yet the code for the tooltips.
Need some coffee. I meant:

Sorry forgot to write my patch is without tooltip change. This, 1. because like this it's possible to uplift to 45 without the probably needed locale strings, 2. I haven't found yet the code for the tooltips.
There is more than one reason to seaparate the arrows into a separate column.
How you can sort on left pointing arrow when list shows left and right arrows attached to a variable list of names?
It may make sense to change the sorting algorithm to show outgoing messages first and incoming second, since each of those is really a different field, so it's a bit strange to interleave them.
Flags: needinfo?(squibblyflabbetydoo)
As the 'Correspondents' column can now shows names of incoming and outgoing, there will be the need to do different types of sorting.
Ability to sort incoming from outgoing and ability to reverse that sort with additional abilities to sort alphabetically.
Ability to select 'show only incoming' and 'show only outgoing'
Ability to sort all alphabetically and the reverse without sorting by incoming/outgoing.

How would the 'Group by Sort' work in cases where there are both incoming and outgoing?
At the moment it sorts alphabetically by date which is probably fine if you do not mind having a mix of incoming and outgoing, but how to set it up so that sorted by incoming, name, date then followed by any outgoing for same name in date order. Just thinking out a loud here :)

If the arrow really was a separate column, then it could be used to sort by incoming or outgoing leaving the actual 'Correspondents' column to sort alphabetically.

Another idea:
Perhaps the Quick Filter Bar could help with this issue and have 'Show only incoming', 'show only outgoing' additional sort icons which are only available if the 'Correspondents' column header is selected. Thoughts ?
Please move sorting and issues not related to arrow appearance to other bugs. Thanks.
As requested, I started a new bug discussing using the icon as a sort mechanism, improving current sort options and using the Quick Filter Bar to aid in any improvements.
https://bugzilla.mozilla.org/show_bug.cgi?id=1267597
Attached patch correspondents.patch v2 (obsolete) — Splinter Review
Found a error in osx file.
Attachment #8744645 - Attachment is obsolete: true
Attachment #8744645 - Flags: review?(squibblyflabbetydoo)
Attachment #8745335 - Flags: review?(squibblyflabbetydoo)
OS: Unspecified → All
Hardware: Unspecified → All
Version: unspecified → Trunk
I would like to keep the left/right direction as it is more in sync with the reply /forward driectional buttons, and also have a monochrome color for the right arrow, just default to black instead of light gray; my _own_ mails in a thread have to "stick out" so they are what needs emphasis

Having the color of the right arrow configurable would be great.

Hovering on the arrow should show the complete from header in a tooltip:

from: name <email>

I will attach a mockup of my alternative suggestion
Here is my (minimal) solution. it would be enough for a quick parsing of a thread to find the emails where I am the author. keep the direction horizontal to not break the reply metaphor. Alternatively we could try a "person" icon for marking the emails coming "from me".
That would also fit with the flat/colorless UI trend :)
(In reply to Axel Grude [:realRaven] from comment #34)
> Created attachment 8746489 [details]
> darke correspondence arrow when I am from
> 
> Here is my (minimal) solution. it would be enough for a quick parsing of a
> thread to find the emails where I am the author. keep the direction
> horizontal to not break the reply metaphor. 

call me flighty, but of all the choices I now like Axel's the best because of the higher contrast
I didn't like this feature at first, but it has grown on me...

Personally, I do like the solid black version, but I would prefer a down arrow for incoming, and an up arrow for outgoing...
(In reply to :aceman from comment #35)
> That would also fit with the flat/colorless UI trend :)

I disagree that we should minimize the use of color here. Thunderbird uses color to indicate the status of items that can change in the UI. For instance, we avoid color in the toolbar buttons because they're (mostly) static. However, the stuff you see in the thread pane is always changing as you get new mail. Hence, we should use color here. (See also comment 1.)

Of course, grey and black are still "colors", but I think using blue and green to match the inbox/outbox would help to further improve the ability for users to scan these fields. It would help if we split the difference here and used dark blue for outgoing and pale green* for incoming. That way, we're providing three ways to distinguish the icons: 1) shape, 2) hue, and 3) brightness/value.

* On Linux, we use yellow for outgoing. Perhaps we should settle on a pair of colors that we use on *all* platforms.
Comment on attachment 8745335 [details] [diff] [review]
correspondents.patch v2

r- for now because I think we still need to discuss things a bit more.
Attachment #8745335 - Flags: review?(squibblyflabbetydoo) → review-
Here are the things I think we should do in this bug:

1) Settle on colors that we want to use to mean "incoming" and "outgoing" and use them in both these icons and the inbox/outbox icons. Possibly use the same colors on all platforms.

2) Decide whether to use up/down (with/without a "bin") or left/right. It seems like it's about 50/50 now.

3) Figure out if we can add a tooltip just for the icon.
(In reply to Jim Porter (:squib) from comment #38)
> (In reply to :aceman from comment #35)
> > That would also fit with the flat/colorless UI trend :)
> 
> I disagree that we should minimize the use of color here.

Looks like the irony was not pronounced enough.
(In reply to Jim Porter (:squib) from comment #40)
> Here are the things I think we should do in this bug:
> 
> 1) Settle on colors that we want to use to mean "incoming" and "outgoing"
> and use them in both these icons and the inbox/outbox icons. Possibly use
> the same colors on all platforms.

OS X has no arrows on the "bins". But I'm okay with changing the color on Linux.

> 2) Decide whether to use up/down (with/without a "bin") or left/right. It
> seems like it's about 50/50 now.

I'm more for the left/right.

> 3) Figure out if we can add a tooltip just for the icon.

Please in a new bug. New strings would make it impossible to land on 45.
(In reply to :aceman from comment #41)
> (In reply to Jim Porter (:squib) from comment #38)
> > (In reply to :aceman from comment #35)
> > > That would also fit with the flat/colorless UI trend :)
> > 
> > I disagree that we should minimize the use of color here.
> 
> Looks like the irony was not pronounced enough.

Heh. I never know sometimes. It took a lot of words to keep the colors we *do* have now.

(In reply to Richard Marti (:Paenglab) from comment #42)
> OS X has no arrows on the "bins". But I'm okay with changing the color on
> Linux.

As long as the look is consistent on each platform, I'm happy.

> > 2) Decide whether to use up/down (with/without a "bin") or left/right. It
> > seems like it's about 50/50 now.
> 
> I'm more for the left/right.

Maybe we could make mockups of a few options and just have folks vote on it?
I would just like to weigh in on this issue as a longtime user of Thunderbird with substantial business use each day, and literally close to a hundred folders which a I have created for each client/matter.  I have been using one of the add-ons which gave similar functionality, but I would of course prefer to use the built in features rather than a plugin. 

As I place all mail for each matter in its own folder, since the update, as others have commented, I do find it very difficult to quickly distinguish my outgoing mail from the incoming.  

I do prefer the left-right setup, but shading is an absolute to quickly, visually sort entries -  say as scrolling through a particularly long folder. I do not think making the icons larger or using bins necessarily helps, just as long as the arrows are quickly distinguishable. 

As an aside, one of the features that could be configured in the add-on was to change the font of the correspondent to bold or italic. In my setup, my sent messages were in italic. That was very helpful.
Agree with comment 44. There is a model for this already in the excellent visual and technical design of the Show InOut[1] extension. It even has 4 levels of information packed into its 'arrows'.

1. The visual indicator should be a separate column. Sortable and hideable.
2. Colors are a distraction and should not be used. Shapes and font-weight/opacity are better.

[1] https://addons.mozilla.org/en-US/thunderbird/addon/show-inout
(In reply to alta88 from comment #45)
> 2. Colors are a distraction and should not be used. Shapes and font-weight/opacity are better.

That's not only a matter of opinion but also of accessibility. The color adds an important cue for recognizing the symbol, e.g., for people having visual problems distinguishing shapes.

I'm not sure what you have in mind regarding font-weight/opacity, but that might equally help.
(In reply to rsx11m from comment #46)
> I'm not sure what you have in mind regarding font-weight/opacity, but that
> might equally help.

That sounds like what I had in mind regarding brightness/value. Assuming a white background, a dark icon will draw the eye more.

This also suggests another important point: we should be careful with monochromatic icons, since they might not look good on other background colors. Some people need to use dark backgrounds to help with accessibility or even just to reduce eyestrain. We might be able to use theme-derived colors with SVG icons, but using colorful icons like :Paenglab showed would be another good strategy.
(In reply to Jim Porter (:squib) from comment #47)
> (In reply to rsx11m from comment #46)
> > I'm not sure what you have in mind regarding font-weight/opacity, but that
> > might equally help.
> 
> That sounds like what I had in mind regarding brightness/value. Assuming a
> white background, a dark icon will draw the eye more.
> 
> This also suggests another important point: we should be careful with
> monochromatic icons, since they might not look good on other background
> colors. Some people need to use dark backgrounds to help with accessibility
> or even just to reduce eyestrain. We might be able to use theme-derived
> colors with SVG icons, but using colorful icons like :Paenglab showed would
> be another good strategy.

AS regards hard coding colors - that's one of the reasons why I would ultimately like to see a color choice (an rgb[a] value in the config database) which may default to black. And monochrome icons can be supplied with a negative outline (e.g. black arrow with white outline) to remain visible on high-contrast displays.

Secondly about the arrow orientation, regardless of personal preference there is a reason why side-ways arrows are better:

in Thunderbird we are using the vertical direction very often to signify order or time. For instance the move to next (unread) mail / folder arrows go up and down, and the emails are usually ordered by date vertically. On top of that there are also a lot of widgets that use the vertical (triangle) chevron, for instance drop down boxes, vertical scrollbars etc. So I find the vertical arrow metaphor (upload download) not that useful for Thunderbird, as it is just used too many times already. 

If we still choose to use it we must at least include a "tray" element to provide context, like in Paenglab's examples.

The horizontal arrows are already used for actions like reply and forward, so I still think the current arrow metaphor makes sense, as long as we can emphasize the emails written by the mailbox owner.
Along the lines of accessibility, let's be concerned about all modes, not just visual
The visual modes are the ones we can easily implement for 45esr. The other needs more investigation and maybe also additional strings which is almost not possible for esr.
Attached image proposals for voting
Let's try the voting.

1 is left/right arrows
2 is up/down arrows
3 is up/down arrows with bin

I vote for 1
(In reply to Axel Grude [:realRaven] from comment #48)
> AS regards hard coding colors - that's one of the reasons why I would
> ultimately like to see a color choice (an rgb[a] value in the config
> database) which may default to black. And monochrome icons can be supplied
> with a negative outline (e.g. black arrow with white outline) to remain
> visible on high-contrast displays.

Maybe the icons can be pure white and there is a css rule to change the color/hue/something to the desired color? Then that can be part of the theme.
(In reply to :aceman from comment #52)
> Maybe the icons can be pure white and there is a css rule to change the
> color/hue/something to the desired color? Then that can be part of the theme.

I use in my patch already svg icons and platform specific colors can be made like I've did for the toolbar icons.
Assuming you are using a folder for both sent and received:
I do not think you need an icon or  different icon for both.

Consider this:
If only the 'incoming' mail had a black or bold outline arrow icon.
Then anything without an arrow must be what you sent. 
A gap in a vertical line of horizontal pointing arrows actually stands out very well.
It would also resolve the issue of needing different colours for sent and received.

So you could improve readibility etc by just removing the icon for eg: Sent


Agree Contrast is important for:
*visibility/readibilty for those with eyesight issues.
*ability to be easily distinguish between the two.

Ability to set own colour preference is a good idea.
(In reply to Jim Porter (:squib) from comment #40)
> 2) Decide whether to use up/down (with/without a "bin") or left/right. It
> seems like it's about 50/50 now.

I replied to the bugzilla emial instead of here, so repeating here...

Actually thinking about it a bit more, I think there is an even better
way...

Why not have the 'To' arrow be a right pointing arrow on the left side
of the correspondent, as it is now - ie, pointing toward the
correspondent - but have the 'From' arrow *also* be a right pointing
arrow, but on the *right* side of the correspondent - ie, pointing *away
from* the correspondent.

> 3) Figure out if we can add a tooltip just for the icon.

I do like the idea of the tooltip as well, I find them very useful in cases like this.
(In reply to Anje from comment #54)
> Assuming you are using a folder for both sent and received:
> I do not think you need an icon or  different icon for both.
> 
> Consider this:
> If only the 'incoming' mail had a black or bold outline arrow icon.
> Then anything without an arrow must be what you sent. 
> A gap in a vertical line of horizontal pointing arrows actually stands out
> very well.
> It would also resolve the issue of needing different colours for sent and
> received.

I like this idea even more - less clutter. Just reverse the logic and only have the arrow on the "Outgoing" emails, then in a conversation you you will likely have even less icons than the other way round. The tooltip might still be useful as  it could tell which email address I have used...

Also - voting: I vote 1
I've created a Google poll for us to tally the results: http://goo.gl/forms/jZz29IYBAB

I'll also post this on tb-planning. Do you think I should post it to mozilla.support.thunderbird as well?
(In reply to Richard Marti (:Paenglab) from comment #51)
> 1 is left/right arrows
> 2 is up/down arrows
> 3 is up/down arrows with bin

These all look far too cluttered to me, especially 3. 

Why do you need the arrows at all? Surely the user will recognise their own email address.

As a real-world example, the fastmail web app does not distinguish at all between the user's email and incoming email in its correspondents-like column, and it doesn't seem to be a problem.

So much visual noise - it's the kind of thing you could at least make opt-in.

In most folders, I suspect all the arrows will be pointing in the same direction, making them meaningless.
(In reply to aleth [:aleth] from comment #58)
> These all look far too cluttered to me, especially 3. 

Tat's why in the implementing bug the the gray arrows are choosen.

> As a real-world example, the fastmail web app does not distinguish at all
> between the user's email and incoming email in its correspondents-like
> column, and it doesn't seem to be a problem.

Could you add a screenshot of it to show how this looks?
(In reply to aleth [:aleth] from comment #58)
> Why do you need the arrows at all? Surely the user will recognise their own
> email address.

The user's own email address isn't shown in the Correspondents column. That's the whole point. It always shows the *other* person in the conversation.
(In reply to Anje from comment #54)
> Assuming you are using a folder for both sent and received:
> I do not think you need an icon or  different icon for both.
> 
> Consider this:
> If only the 'incoming' mail had a black or bold outline arrow icon.
> Then anything without an arrow must be what you sent. 

Great!
However most people receive more emails than they send.
How about a dot in front of the sent emails, empty for received.
Then the own emails are easily visible as such at a glance.
And the majority without a dot is just normal incoming email.
Here's a potential refinement: we already know when a folder is incoming or outgoing (e.g. Sent, Drafts). If a folder is normally incoming, only show an arrow on outgoing messages; if it's normally outgoing, only show an arrow on incoming messages.
(In reply to Jim Porter (:squib) from comment #62)
> Here's a potential refinement: we already know when a folder is incoming or
> outgoing (e.g. Sent, Drafts). If a folder is normally incoming, only show an
> arrow on outgoing messages; if it's normally outgoing, only show an arrow on
> incoming messages.

Isn't it confusing when the rule is different in different folders?
And it does not work for people who move all emails to topic-folders,
they are neither normally in, nor normally out.
(In reply to hartnegg from comment #63)
> Isn't it confusing when the rule is different in different folders?

That's why they'd have different icons.

> And it does not work for people who move all emails to topic-folders,
> they are neither normally in, nor normally out.

I think Thunderbird considers those to be incoming folders. The only outgoing folders a user would have are ones like Drafts and Sent. In those folders, with the logic in comment 62, you'd probably *never* see a <- arrow.
(In reply to Richard Marti (:Paenglab) from comment #59)
> (In reply to aleth [:aleth] from comment #58)
> > These all look far too cluttered to me, especially 3. 
> 
> Tat's why in the implementing bug the the gray arrows are choosen.

Yes, that makes sense.

I think comment 62 would make an interesting experiment.

> > As a real-world example, the fastmail web app does not distinguish at all
> > between the user's email and incoming email in its correspondents-like
> > column, and it doesn't seem to be a problem.
> 
> Could you add a screenshot of it to show how this looks?

It's not quite the same concept, given comment 60, but here is a screenshot: https://blog.l0cal.com/images/fastmail-ux.png
(In reply to aleth [:aleth] from comment #65)
> (In reply to Richard Marti (:Paenglab) from comment #59)
> > (In reply to aleth [:aleth] from comment #58)
> > > These all look far too cluttered to me, especially 3. 
> > 
> > Tat's why in the implementing bug the the gray arrows are choosen.
> 
> Yes, that makes sense.

I could also try to reduce the saturation of the blue and green arrows to make them less prominent but still distinguishable by color.

> I think comment 62 would make an interesting experiment.

Yes, but my skills are too low to implement it
(In reply to Jim Porter (:squib) from comment #64)
> (In reply to hartnegg from comment #63)
> > Isn't it confusing when the rule is different in different folders?
> 
> That's why they'd have different icons.

But the whole point of this suggestion is that there should be no need to distinguish two different symbols, but have only one.

If it were a separate column instead of part of the new column, that column could be removed in the sent-folder, where it would be useless, because every email there would have the symbol.
Comment on attachment 8747020 [details]
proposals for voting

This is utterly confusing.
Richard tells me that the first line of blue arrows all means: Message *to* Richard.
How can a message to Richard come out of a tray next to Richards name?

The second line of green arrows all mean: *From* Nevin?
Impossible, since the rightmost green arrow goes into a tray next to Nevin's name, that must be *to* Nevin, it looks like Nevin's inbox, so it must be *to* Nevin.

If the rightmost icon on the second line means *from* Nevin, that we have a real problem since no one will understand that.
(In reply to Richard Marti (:Paenglab) from comment #66)
> (In reply to aleth [:aleth] from comment #65)
> > I think comment 62 would make an interesting experiment.
> 
> Yes, but my skills are too low to implement it

I'm sure e.g. aceman knows enough about folders to be able to help with this.
Flags: needinfo?(acelists)
Yes, surely that can be done if really needed.
Flags: needinfo?(acelists)
(In reply to Jorg K (GMT+2) from comment #68)
> If the rightmost icon on the second line means *from* Nevin, that we have a
> real problem since no one will understand that.
Apparently the explanation is:
The down-arrow is a download and it's *my* inbox, so a download from Nevin into my inbox. Hmm.
(In reply to Jorg K (GMT+2) from comment #71)
> Apparently the explanation is:
> The down-arrow is a download and it's *my* inbox, so a download from Nevin
> into my inbox. Hmm.

Yeah, they're simplified versions of the inbox/outbox icons.
Thinking about it more, I'd probably be ok with only having an icon for outgoing messages (and not doing the thing I said in comment 62). I'm not sure if we should give that icon some color or not, or if the icon should point up or right, though.

If we do this, we really need to change the left margin on the Correspondents header to line up with the *text* of each row, like how we do with the Subject header.
(In reply to Jim Porter (:squib) from comment #73)
> Thinking about it more, I'd probably be ok with only having an icon for
> outgoing messages (and not doing the thing I said in comment 62). I'm not
> sure if we should give that icon some color or not, or if the icon should
> point up or right, though.

Then all messages in the sent folder have an icon in the same direction. I think it would be better to not show one in this case. Only show icons in the non-usual way.

> If we do this, we really need to change the left margin on the
> Correspondents header to line up with the *text* of each row, like how we do
> with the Subject header.

recorded.
(In reply to Richard Marti (:Paenglab) from comment #74)
> (In reply to Jim Porter (:squib) from comment #73)
> > Thinking about it more, I'd probably be ok with only having an icon for
> > outgoing messages (and not doing the thing I said in comment 62). I'm not
> > sure if we should give that icon some color or not, or if the icon should
> > point up or right, though.
> 
> Then all messages in the sent folder have an icon in the same direction. I
> think it would be better to not show one in this case. Only show icons in
> the non-usual way.

As someone who lives in Inbox which (by choice) for me has BOTH incoming and outgoing messages, I like the direction this is going.  So for Inbox and Outbox, only have arrows for messages that do NOT match what the folder is about.

(BTW, the vibe and discussion has been good, but let's also not rush the process. There's no near-term deadline here.)
(In reply to Jim Porter (:squib) from comment #73)
> Thinking about it more, I'd probably be ok with only having an icon for
> outgoing messages (and not doing the thing I said in comment 62). I'm not
> sure if we should give that icon some color or not, or if the icon should
> point up or right, though.
> 
> If we do this, we really need to change the left margin on the
> Correspondents header to line up with the *text* of each row, like how we do
> with the Subject header.

I think this makes a lot of sense. Looking through a folder of messages today looking for ONE message I sent to someone who has sent me about twenty messages (along with all the other correspondents) I was trying to visualize the different icon suggestions. I think the purest, most uncluttered layout would be an arrow just for sent messages. As Jim said, I have no real preference on up/down or color.
Bug 36489 comment 85 (2006-08-29):
"My former email client, Claris Emailer, uses a combined From/To column which was very intuitive. For incoming messages the sender display name is listed in the From/To column; for outgoing messages, a boldface "To: " is prefixed to the recipient name(s) in the From/To column. This style would require even less UI effort than the icon style above."

 Only having an object in the UI to denote "sent from me to correspondent" emails is the simplest and easiest to read.

 I note that there's a "Correspondent" column which prefixes "From:" and "To:" to every email. When was that introduced? That could be easily hacked to give prefixes of "" and "To:" which would be a really big improvement.
(In reply to jwq from comment #77)
>  I note that there's a "Correspondent" column which prefixes "From:" and
> "To:" to every email. When was that introduced? That could be easily hacked
> to give prefixes of "" and "To:" which would be a really big improvement.

Are you sure this doesn't come from an add-on?
(In reply to Jim Porter (:squib) from comment #78)

 You're right, it does come from an addon, I have the Show In/Out extension installed (and had forgotten). I second the suggestions in Comment 44 and Comment 45 of copying the UI from the extension, particularly if the built-in functionality retains user-configurable prefix functionality.
After some experimentation, I'd recommend:

1. Rename the column heading "From/To". Advantages: accurately describes the data that is displayed in the column; doesn't conflict with the Show In/Out extension; easily localisable.

2. Default to using boldface text to indicate from/to instead of icons (allowing icons as user-configurable pref, if desired). Advantages: the meaning of text is clear while icons are ambiguous; text can reference the column name to improve the intuitive nature of the GUI; easily localisable.

3. Default to indicate only one direction of correspondence, leaving the other un-prefixed. The obvious one would be "To:". Advantages: Much higher contrast in the GUI between "From" or a "To" because there is no need to read text or arrow direction to determine the message's direction of correspondence, leading to improved ease-of-use.

The column name "Correspondents" is too wooly a term, as evidence I cite the extended debate in various bugs. Follow the KISS principle and name the column after the data that it displays.
This is a screenshot of the proposal to show the arrow only on message which are in the non-usual folder direction. Here the inbox with arrows on sent messages.
FWIW: One reason for having the "Correspondents" column was to offer something similar to the "Who" column in Eudora(†) (bug 359270, was duped to bug 36489). Eudora didn't have any icons in that column:
http://static.digit.in/fckeditor/uploads/file/OSE_Mac_UI.png

That motivates a somewhat minimal solution.

<off topic>
Diving into the quirky old past, we read here http://emailoverload.com/eudora/html/OEO-Eudora-4.html that Eudora could 1) sort multiple columns and 2) select multiple messages with <alt><click>, requested as bug 1265090.
</off topic>
(In reply to Richard Marti (:Paenglab) from comment #81)
> Created attachment 8747415 [details]
> unusualDirectionArrow.png
> 
> This is a screenshot of the proposal to show the arrow only on message which
> are in the non-usual folder direction. Here the inbox with arrows on sent
> messages.

This one I like best so far, very easy on the eyse, monochrome compliant and immediately draws attention to the fact that I have written that email. by the way does this take into a account all my outgoing email addresses? I often filter mail across servers so may have mails from my indigo address being in the gmail account.
(In reply to Richard Marti (:Paenglab) from comment #81)
> This is a screenshot of the proposal to show the arrow only on message which
> are in the non-usual folder direction. Here the inbox with arrows on sent
> messages.

Looks much cleaner, but the arrows pointing to the right in their own column can make it appear like those messages are being pointed at (as opposed to indicating "sent to"). So it would be better to not have the arrows in their own column, but just in front of the name. (One could experiment also with just using a string, "To: ", as suggested in comment 80.)
Personally, I preferred the more lightweight arrow style from the existing code to the thick arrow used here.
The indicator should be a separate column for these reasons:

1. Some (many?) users will detest the occupation of this precious real estate, and will want it gone; this is easily done as a column.

2. Some may want to dnd move the column to another location, away from the name. For example, I find it much more meaningful and easier visually when it is placed with the other iconic columns. Putting it with the name forces comprehension of that name, which is not what should happen when scanning the list.

3. As a column, sorting by the indicator (and secondarily by name, or any other column) is possible. Who doesn't think sorting by the indicator will be a request?

4. It is possible to Group By the indicator if it's a column.

5. The indicator column header (very small, as iconic) should have a tooltip explaining itself, in more detail than just 'Click to sort' (unwanted tooltips anywhere else would be very annoying).

It doesn't seem worth implementing Correspondents in a far less featureful manner than Show In/Out. The difference between a message as To, as Cc, as part of a group/llist; the ability to sort/group; the custom labels -- these are all very valuable
I think we wanted to do that in a separate bug for trunk (as it is more invasive and would need strings too). But I do not see it filed yet.
A quick mock-up of the text version (using the Show In/Out extension). It would look a lot better with the "To: " prefix always in boldface.
(In reply to jwq from comment #87)
> Created attachment 8747672 [details]
> From/To column with outgoing messages only prefixed with "To: ".
> 
> A quick mock-up of the text version (using the Show In/Out extension). It
> would look a lot better with the "To: " prefix always in boldface.

I like this idea (though I suspect it's actually better without boldface "to").

Whatever the ultimate solution chosen, care should be taken to ensure it works well with a11y. I don't know if that's the case with the current Correspondents column that uses arrows?
I don't think we can mix text formatting in a single column in a XUL tree. In any case, boldface means "unread" in TB, so using bold for a correspondent would be confusing. The "To:" text is also a lot harder to scan than an arrow that's only shown for outgoing: see attachment 8747415 [details].
Another problem with using "To:" is that when we reland bug 522886, we'll show all the recipients (To, Cc, and Bcc), not just To.

Finally, it looks like we can't have tooltips: see bug 421167. I tried some ideas and can't even get them to work for icon-only columns.
Jim, do you agree we should try to implement attachment 8747415 [details]?
(In reply to Jim Porter (:squib) from comment #90)
> Finally, it looks like we can't have tooltips: see bug 421167. I tried some
> ideas and can't even get them to work for icon-only columns.

If you can't at least add aria-labels, you can't ship arrows as a default if they are the only way to distinguish from/to.
Ricard: Yeah, I think it's a good idea. It's up to you whether you want to keep the icons currently in comm-central or design new icons. If you'd like to show the incoming arrow in outgoing folders, perhaps :aceman could add the necessary logic for you (or I could, in a pinch)?

(In reply to aleth [:aleth] from comment #92)
> If you can't at least add aria-labels, you can't ship arrows as a default if
> they are the only way to distinguish from/to.

It's a little late for that. I don't think *anything* in the XUL tree has proper tooltips/aria-labels. That includes stars, attachments, and reply/forward indicators.
(In reply to Jim Porter (:squib) from comment #89)
> The "To:" text is also a lot harder to scan than an arrow that's only 
> shown for outgoing: see attachment 8747415 [details].

 There's no fundamental reason why that should be so.

 I note the icon version has the recipient display names indented, so let's compare like with like in my second mock-up, attached, in which the display names are indented.

FWIW, boldface of the "To:" prefix made it "easy to scan" in the original Claris Emailer UI.

(In reply to Jim Porter (:squib) from comment #90)
> Another problem with using "To:" is that when we reland bug 522886, we'll
> show all the recipients (To, Cc, and Bcc), not just To.

 I don't see that as a problem, the "To:" prefix can be easily understood by non-technical end-users to mean "all recipients" and not literally "the contents of the To: field of the email header".

 The only advantage an arrow icon has in this situation is that its meaning is vague... but that's also it's disadvantage. Many of the comments protesting the forced "upgrade" to a Correspondents column UI pointed out that the meanings of the arrows are unclear and confusing. The debate in this bug strongly indicates there is no one clear best choice for an arrow icon.

 It's reasonable to expect more users will understand the text "To:" than will understand arrow icon meanings.

 Text is easier to localise into other cultures which don't necessarily share your reading of "grey arrow pointing right", and those using reader software for the vision-impaired can't read arrow icons (see the post to tb-planning) but can read text.
(In reply to jwq from comment #94)
>  I note the icon version has the recipient display names indented, so let's
> compare like with like in my second mock-up, attached, in which the display
> names are indented.

I don't think there's a way to do this with XUL trees.

> FWIW, boldface of the "To:" prefix made it "easy to scan" in the original
> Claris Emailer UI.

Nor this, as I mentioned above in comment 89.
"To" might also be a bad choice for some locales, e.g. French, which uses "Destinataire" for the "To:" header. That would be way too long and would end up hiding a lot of the important text (the recipient's name).

While a French localizer might be able to use "à" instead, I'm not sure if that's the most-comprehensible choice for a native speaker, and I know even less about other languages with long strings for the "To:" header, such as Finnish and Ukrainian.
(In reply to Jim Porter (:squib) from comment #95)
> I don't think there's a way to do this with XUL trees.

 Sorry to spam the bug, but I don't understand why this isn't possible: I mocked this up by hacking the column header of the "Show In/Out" add on and performed the prefixing using the add on prefix preferences. The screenshot is of my TB 45 running the hacked "Show In/Out".

 Are there some thing which can be accomplished in extensions but which can't be accomplished in XUL trees?

> Nor this, as I mentioned above in comment 89.

 Is there an RFE for mixing text formatting in a single column in a XUL tree? :-)

(In reply to Jim Porter (:squib) from comment #96)
> "To" might also be a bad choice for some locales, e.g. French, which uses 
> "Destinataire" for the "To:" header.

 Localisation of a prefix in this column isn't about the header text, it's about - as you yourself go on to point out for French - selection of locale-appropriate short version for the column rows. I daresay such short prefixes exist in most languages.

 To give a localisation example, text would likely work much better for Japanese which by convention place the honourific and the equivalent of "To" on the right of the recipient's name not on the left. How do you expect an arrow pointing right on the right of the recipient name is to be interpreted in Japanese culture? An arrow pointing right on the left may look foreign. Text would be immediately comprehensible and culturally appropriate.

BTW, indenting the display names and the column header to make room for arrow icons (or text) has the consequence that, when the arrow is shown only for outgoing messages and the folder being displayed has no such messages near the top of the pane, there's white space on the left of the "Correspondents" column which is incongruent with the look-and-feel of the rest of the UI because it's neither left nor right aligned.
(In reply to jwq from comment #97)
> (In reply to Jim Porter (:squib) from comment #95)
> > I don't think there's a way to do this with XUL trees.
> 
>  Sorry to spam the bug, but I don't understand why this isn't possible: I
> mocked this up by hacking the column header of the "Show In/Out" add on and
> performed the prefixing using the add on prefix preferences. The screenshot
> is of my TB 45 running the hacked "Show In/Out".

What did you do to line them up? If you say that you used space characters to indent the incoming messages, know that we can't accept that in a patch, since it will only work if users have the same font settings as the developers. (You could also use some CSS to add a left margin only for incoming messages, but that has the same issue.)

>  Is there an RFE for mixing text formatting in a single column in a XUL
> tree? :-)

No, and there won't be, since Mozilla has deprecated XUL and is in the process of removing it. We'll probably have to remove XUL trees from Thunderbird one day too, but that's a huge project.

> BTW, indenting the display names and the column header to make room for
> arrow icons (or text) has the consequence that, when the arrow is shown only
> for outgoing messages and the folder being displayed has no such messages
> near the top of the pane, there's white space on the left of the
> "Correspondents" column which is incongruent with the look-and-feel of the
> rest of the UI because it's neither left nor right aligned.

There's no incongruence. That's how the Subject column works too. There's space pre-allocated for the replied/forwarded icon.
(In reply to Jim Porter (:squib) from comment #98)
> What did you do to line them up?

 Yes, I used space characters. Space characters are within my abilities. It is a mock-up which is limited by my capabilities, not a proposed patch.

 One obvious way to get around the mixed text format limitation would be to use an image of the text in boldface as the icon. Yes, font changes would be a problem. I suppose the image could be regenerated when the UI font is changed? Yes, complex.

> There's no incongruence. That's how the Subject column works too. There's
> space pre-allocated for the replied/forwarded icon.

 Thanks for pointing that out, I missed that one because the indentation space is rather small by comparison to the "Correspondent" column - which is why it stands out as incongruent.
(In reply to jwq from comment #99)
> > There's no incongruence. That's how the Subject column works too. There's
> > space pre-allocated for the replied/forwarded icon.
> 
>  Thanks for pointing that out, I missed that one because the indentation
> space is rather small by comparison to the "Correspondent" column - which is
> why it stands out as incongruent.

It should be the same number of pixels wide. Note that we'll also make sure the "Correspondent" header lines up with the text, as the "Subject" header does. See attachment 8747415 [details].
RE comment 85 and responce 86
Sorting issues in a new bug was filed as requested and mentioned in comment 31
https://bugzilla.mozilla.org/show_bug.cgi?id=1267597
Attached patch correspondents.patch v3 (obsolete) — Splinter Review
With the help of aceman this patch shows now only an arrow when a message is outgoing in a inbox or incoming when in a outbox.

I'm using now the arrow color like in attachment 8747415 [details].

Thanks again for aceman's help.
Attachment #8745335 - Attachment is obsolete: true
Attachment #8750903 - Flags: review?(squibblyflabbetydoo)
(In reply to Richard Marti (:Paenglab) from comment #102)
> Created attachment 8750903 [details] [diff] [review]
> correspondents.patch v3
> 
> With the help of aceman this patch shows now only an arrow when a message is
> outgoing in a inbox or incoming when in a outbox.
> 
> I'm using now the arrow color like in attachment 8747415 [details].
> 
> Thanks again for aceman's help.

What about the other folders? I try to filter 99% of my mails to folders and do not use the Sent folder [use copy sent to current instead] but really keep threads together. Still think it should also only show the "outgoing" arrow in all other folders. (usually there is less outgoing mail in conversations so less clutter). 

Also, incoming mail in an outbox? Who filters their mail into the sent mail folder?
(In reply to Axel Grude [:realRaven] from comment #103)
> (In reply to Richard Marti (:Paenglab) from comment #102)
> > With the help of aceman this patch shows now only an arrow when a message is
> > ....[is] incoming when in a outbox.
> 
> Also, incoming mail in an outbox? Who filters their mail into the sent mail
> folder?

To clarify: if outbox=sent then I would expect it to have _only_ outgoing mail anyway, so I wouldn't expect any mails with "incoming" arrows.
(In reply to Axel Grude [:realRaven] from comment #103)
> What about the other folders?
If you look into the patch, all other folders (except Outbox, Sent, Drafts, Templates) are considered incoming.

> I try to filter 99% of my mails to folders and
> do not use the Sent folder [use copy sent to current instead] but really
> keep threads together. Still think it should also only show the "outgoing"
> arrow in all other folders.
Yes, so as all are incoming, only the sporadic outgoing message in them gets the arrow. Other messages have no arrow.

> Also, incoming mail in an outbox? Who filters their mail into the sent mail
> folder?
Yes, therefore if a sporadic incoming message gets into Sent (Sent is not the same as Outbox (Unsent)), it gets the arrow. Outgoing messages do not get it.
I haven't seen it mentioned, but in my opinion, the Trash should always contain both arrows (since it will contain both incoming and sent).
That's doable if it is agreed upon.
I don't think that belongs in this bug, given that the default columns for Trash have always been the same as that of an incoming folder. This patch just makes it easier to restore things to their default state (or something like it, really).

I also don't agree that Trash should be treated specially, since it's certainly not the only folder that contains incoming and outgoing messages. Anyone who enables placing replies in the folder of the original will also have incoming + outgoing in one folder. Likewise, any Gmail user will have an All Mail folder with incoming + outgoing messages. For users with folders like that, I think many would prefer to just see From (or Correspondents), and if not, they can tweak the setting per-folder.
(In reply to Jim Porter (:squib) from comment #108)
> I don't think that belongs in this bug, given that the default columns for
> Trash have always been the same as that of an incoming folder.

True it has been, but I actually was thinking I was in the related bug 562266, about honoring special folders, where I added two comments (7 in October 2010 and 10 last week) specifically about including the Trash, since it most certainly is a 'special folder'.

> I also don't agree that Trash should be treated specially, since it's
> certainly not the only folder that contains incoming and outgoing messages.

It is the only folder *guaranteed* to contain both (unless you bypass or otherwise don't use it).

> Anyone who enables placing replies in the folder of the original will also
> have incoming + outgoing in one folder

Yes, you can do lots of things with filters.

But again, the Trash *is* a special folder, and it is guaranteed - if you are using it - to contain both incoming and sent messages.
Attached patch correspondents.patch v4 (obsolete) — Splinter Review
Updated to tip after unprefix bug 1272606.
Attachment #8750903 - Attachment is obsolete: true
Attachment #8750903 - Flags: review?(squibblyflabbetydoo)
Attachment #8752577 - Flags: review?(squibblyflabbetydoo)
Comment on attachment 8752577 [details] [diff] [review]
correspondents.patch v4

This patch makes TB crash in "Search Messages" dialog.

The cause is this code:

+    m_folder->IsSpecialFolder(nsMsgFolderFlags::SentMail | nsMsgFolderFlags::Queue |
                              nsMsgFolderFlags::Drafts | nsMsgFolderFlags::Templates,
+                              true, &folderOutgoing);

I think it's because the search dialog is in no folder and this one tries to read the actual folder.

Aceman, please could you look into this?
Flags: needinfo?(acelists)
Attachment #8752577 - Flags: review?(squibblyflabbetydoo)
Attached patch correspondents.patch v5 (obsolete) — Splinter Review
Fixed the crash in "Message search" dialog. Thanks to aceman.
Attachment #8752577 - Attachment is obsolete: true
Flags: needinfo?(acelists)
Attachment #8752893 - Flags: review?(squibblyflabbetydoo)
> Yes, therefore if a sporadic incoming message gets into Sent
> (Sent is not the same as Outbox (Unsent)), it gets the arrow. Outgoing messages do not get it.

Can we keep it consistent?

At least the "written by me" icon should be there always, even in "Sent" folder. The icon needs to be reach muscle memory for the user. In order to do that, it needs to be there always, independent of situation, for all messages written by the user.

If you're deciding to hide the "incoming" icon in normal folders, and but do want to show it in Sent folders, that's fine.
Please do not use an arrow to signify "written by me", esp. if the icon is there only for some messages. I (as a user) would think it would mean "Downloaded" (down arrow) or "Important" (right arrow), and it would create even more confusing than we have now.

If the only icon was a pencil, that would be clearer. Please make it a red pencil icon, so that
a) messages written by me stand out visually
b) the meaning of the icon is immediately clear
c) the icon can reach muscle memory and the user doesn't have to consider state or column header to understand it.
I have no strong opinion on whether we should invert the logic for outgoing folders, but I'm not sure a pencil is the right icon. I'd have to see some examples, but at the size we're dealing with, a pencil might be hard to understand. (Note that we have no ability to use tooltips to explain the icon, from what I can tell.)

Another option is a postage stamp, but that doesn't really make sense for drafts/templates, which haven't been sent yet.
(In reply to Jim Porter (:squib) from comment #115)

> Another option is a postage stamp, but that doesn't really make sense for
> drafts/templates, which haven't been sent yet.
I have seen the postage stamp metaphor in postbox and in Tb Linux themes; but I found it slightly harder to understand (stamp = ready to send / send out?) somehow this just being a part of the physical mail metaphor (like the envelope) didn't seem intuitive enough for an action. As regards the pencil, this probably has the same weakness except that it is a more known physical object (in an age of majority electronic communication, stamps are not used as widely); at last the pencil has the connotation of writing (my own) emails, so in my mind it is slightly more personal.

Another alternative may be the "person" icon which could be a metaphor for (my) identity. But again it is already used for the address book, so it may lead to more confusion as it could be mistaken for "author is known".

Regardless of the imperfection of real world metaphors, once they are learned they are not that hard, but they have to be -u-n-i-q-u-e- distinguishable within a context; that's one of the things that makes arrows so confusing as they can signify so many things (hierarchy, time, transition, order, emphasis) their universality is what makes them a bad metaphor.
My preference would be to use formatting like that suggested by Axel Grude in comment #34, with the bolding on messages that are the exception. 

Other comments:

1. rsx11m in Comment #46 mentioned colour for accessibility, but that is not accessible to people who are colourblind. Contrast works much better (such as Axel's suggestion in comment #34).

2. Jim Porter in Comment #38 mentioned that this should be in colour because "Thunderbird uses color to indicate the status of items that can change in the UI." However, you cannot do anything to a message to change whether you are the sender or the recipient, so I disagree that this should use colour.

3. I do not think that the arrows should be in a separate column. If you disable that column then it's even harder to tell who is who in the "Correspondents" column. The alternative would be to restore the from/to column(s) instead of removing the arrows.

4. Calling it "From/To:" as suggested by jwq in Comment #80 could be misleading if you are in neither the From or To line (e.g. if you were cc'd on a message).

5. Richard Marti in Comment #81 (attachment 8747415 [details]) suggested only putting arrows on messages that are the exception to the folder.
5a. If that is done the arrow should be inline to the column, i.e. so that the correspondent's name is indented. If there's one thing I like less than clutter, it's whitespace. This accomplishes the same result as having the "To:" inline without having to worry about localizations. 
5b. However, As aleth pointed out in Comment #84, this can give the impression that the arrow is pointing at the message to highlight it rather than to indicate that it is going to that correspondent. Having gray and black arrows, with the emphasis on the exemption, helps to indicate that the direction of the arrow is the point of the arrow.

6. Not to stir the pot, but if you send a message to yourself, shouldn't there be a double-headed arrow? ;)

- RG>
Comment on attachment 8752893 [details] [diff] [review]
correspondents.patch v5

I know I suggested showing the incoming icon in outgoing folders, but other folks have convinced me, and I think it'd be clearer to always show the outgoing icon* no matter what folder you're in.

* I have no strong opinion about what this icon should look like. The little right arrow is fine by me. If folks don't like it, maybe we could fix that in a followup, since the icon shape is a separate (but related) issue to this one.
Attachment #8752893 - Flags: review?(squibblyflabbetydoo) → review-
Attached patch correspondents.patch v6 (obsolete) — Splinter Review
Patch with only outgoing arrows. This makes in sent folder having mostly all messages showing an arrow.
Attachment #8752893 - Attachment is obsolete: true
Attachment #8765102 - Flags: review?(squibblyflabbetydoo)
Comment on attachment 8765102 [details] [diff] [review]
correspondents.patch v6

Review of attachment 8765102 [details] [diff] [review]:
-----------------------------------------------------------------

Looks good, thanks! See my one comment below. (Note, I didn't run with this patch, but it's only CSS and an image.)

::: mail/themes/shared/mail/icons/InOut.svg
@@ +1,1 @@
> +<?xml version="1.0" encoding="utf-8"?>

Just a minor point: since this icon is only for outgoing messages, we should probably name it something different from "InOut.svg".
Attachment #8765102 - Flags: review?(squibblyflabbetydoo) → review+
Renamed the InOut.svg to correspndents.svg to reflect for what it's used.
Attachment #8765102 - Attachment is obsolete: true
Attachment #8765174 - Flags: review+
https://hg.mozilla.org/comm-central/rev/93878cf7544f
Status: ASSIGNED → RESOLVED
Closed: 4 years ago
Resolution: --- → FIXED
Target Milestone: --- → Thunderbird 50.0
(In reply to Richard Marti (:Paenglab) from comment #121)
> Renamed the InOut.svg to correspndents.svg to reflect for what it's used.
Any reason for this ugly file name? We saved typing one "o"?
Oops, I'll fix it. :(
Can you land with DONTBUILD in the checking comment, please.
Duplicate of this bug: 1344078
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